making cesium-gluconate solution

I need advice on making a 140 mM cesium-gluconate solution. The best I figure is to make a 140
mM CsOH solution and then titrate it to pH7.0 with gluconate. I tried this and am not satisfied.
The pH bounced around 7.0 and never really settled down. There must be a way to calculate
this. Any recommendations?
Thanks
Dennis Churchill
dchurchi at acs.ucalgary.ca
U of Calgary